Large scale study shows extra protein supplementation builds more muscle.
Some small studies have found that protein supplementation did not affect lean muscle mass, whereas many other studies have found that it increased lean muscle mass. However, it’s not until the large-scale studies are published that we get a more definitive answer.
A recent study published in the American Journal of Clinical Nutrition reports that protein supplementation augments lean muscle mass and strength gains in people already consuming a high protein diet. Data from 680 subjects with an age range between 19 and 72 years old were included in the study analysis. The average amount of protein provided by either supplement or diet on training days was 42g. So when the data was collected from all the studies, the results followed.
– Compared to a placebo, protein supplementation augmented the gain in lean muscle mass by 0.69 kilograms (1.5 pounds).
– Protein supplementation was also found to significantly improve 1-RM leg press strength by an average of 13.5 kilograms (29.7 pounds).
– Overall, the results indicate that protein supplementation, primarily consumed around training, is associated with 38 percent greater gains in muscle, and 33 percent greater increases in strength.
Most of the studies involved protein provided right around training. The meta-analysis showed that extra protein had a positive benefit on changes in fat-free mass, muscle size, and strength. The increases in lean muscle mass and strength were found despite the fact that all groups were already consuming a protein intake of around 1.2 grams per kilogram of body weight, which has been considered by some researchers as adequate for maximal increases in muscle size. The average amount of protein that was supplemented on top of the standard diet was 50g. Based on these results, one might question the typical protein recommendations of 1.2g per kilogram, or so to increase muscle size.
Cermak, N.M., et al. Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. Am J Clin Nutr. 96(6):1454-1464, 2012.